Many hearing aid device users are not aware if there is a problem with their device like if the wax filter in the speaker unit is blocked with wax, their battery is flat, the speaker unit Is broken, or if the hearing aid device is placed at the proper position in the ear canal.
Additionally, the users often complain or return their instruments to the HCP or to the manufacture of the hearing aid device, even if there is no real hardware error, like if the wax filter needs changing.
So it would be beneficial if the user himself could test whether the hearing aid is working properly, and if not, then get information of what the actual problem with the instrument is.